Though the currently available HPV vaccines Gardasil and Cervarix can protect you from HPV, they are only available for those ages 9 to 26 and aren’t effective in those who may have already been infected with the targeted HPV types. A new vaccine may one day help those over 26 who already show signs of precancerous lesions. This new vaccine, VGX-3100, may create a similar revolution in HPV treatment as Gardasil produced back in 2006.
HPV-preventive vaccines Gardasil and Cervarix protect you from the cancer-causing types of HPV by having your body form antibodies against proteins on the virus itself – proteins L1 and L2. This would allow for your immune system to target and eliminate the HPV virus before it can cause dangerous cancer-causing changes in your body. However, the vaccines are useless when it comes to those who may have already been infected with the cancerous HPV types. This is because after the virus attacks, it hides in your cells in a way that renders the vaccine’s protection ineffective.
VGX-3100 targets different proteins, E6 and E7, which are found in precancerous cells and biopsies of cervical cancer specimens. Therefore, with this vaccine, your body can be trained to target precancerous cells and eliminate them from your body.
To test this, the researchers took 18 women who have cervical intraepithelial neoplasia grades 2 or 3 – or a type of precancerous change. Those women received three doses of VGX-3100 via electroporation, a shot accompanied with an electric pulse. The participants were asked to evaluate their side effects for 7 days after each dose. Afterward, their immune responses were recorded with blood tests for antibodies against the E6 and E7 proteins.
After the vaccine, the researchers found a stronger immune response to HPV-infected cells. However, future research will tell if this change will actually eliminate all abnormal cells infected with HPV and reduce these women’s risk of developing cervical cancer.
If successful, this vaccine may help some of the 12,000 women in the United States who are diagnosed with cervical cancer every year. However, this vaccine can especially help the growing number of women in developing countries who have less access to HPV testing and regular Pap smears. In fact, cervical cancer is the most common cancer among women in developing countries. There are an estimated 493,000 new cases and 274,000 deaths annually from this cancer.
But before it can help anyone, more research and testing need to be done in order to prove its effectiveness and safety. Though this study is quite groundbreaking, the researchers tested VGX-3100 on a very small number of women.
Since 99.7% of cervical cancers come from prior HPV infection, the best protection from cervical cancer is via regular gynecologic exams, Pap smears, HPV DNA testing, HPV vaccination, and safer sex. Hopefully, this potential new vaccine option will one day help the thousands of women who fall through the cracks and need a second chance.